OBJECTIVE: The aim of this study was to determine the incidence of delayed complications, specifically hemothorax, and functional outcome in patients with isolated sternal fracture discharged from the emergency department (ED) compared to patients with other minor thoracic trauma. METHODS: This prospective cohort study was conducted in four university-affiliated Canadian EDs. Patients ages 16 and older discharged from the ED with an isolated minor thoracic injury were included and categorized as isolated sternal fracture, rib fracture, or no fracture...